File is a utility that classifies arbitrary files of any type mainly by their contents. It is considered standard on most Unix distributions. It can output either human-readable concise descriptions or MIME types for machine handling.

ADODB is a set of advanced PHP database
abstraction classes. It supports MySQL,
PostgreSQL, Interbase/Firebird, Informix, Sybase
SQL Anywhere, Oracle, MS SQL 7 and 2000, SAP DB,
Sybase, DB2, FrontBase, Foxpro, Access, Netezza,
LDAP, ODBTP, ADO, and generic ODBC. A metatype
system is built in, making it possible to figure
out that types such as CHAR, TEXT, and STRING are
equivalent in different databases. It also
features portable database creation,
database-backed session support (with encryption),
SQL performance monitoring, and database health
checks.

LILO is a Boot loader for Linux/x86 and other PC operating systems. It is responsible for loading your Linux kernel from either a floppy or a hard drive and passing control to it. It is capable of booting beyond cylinder 1024 of a hard disk if the BIOS supports EDD packet call extensions to the int 0x13 interface. LILO can also be used to boot many other operating systems, including DOS, Windows (all versions), OS/2, and the BSD variants. The LILO distribution includes full source, documentation and support files.

This is a PHP class that attempts to validate a given e-mail address at four levels: matching the address against a RFC compliant regular expression; checking whitelists and blacklists of domains with typing mistakes, disposable email addresses, and temporary and fake domains; verifying the existence of the destination SMTP server by verifying the respective DNS MX record; and connecting to that server to see if the given address is accepted as a valid recipient. The class also features a debugging output option that lets you see the remote SMTP server connection and data exchange dialog to see the real cause why an apparently valid address may not be accepting messages.

Usermin is a Web interface that can be used by any
user on a UNIX system to easily perform tasks like
reading mail, setting up SSH, or configuring mail
forwarding. It can be thought of as a simplified
version of Webmin designed for use by normal users
rather than system administrators.

Sudo (su "do") allows a system administrator to give certain users (or groups of users) the ability to run some (or all) commands as root while logging all commands and arguments. Sudo operates on a per-command basis, it is not a replacement for the shell.